The present invention relates to determining the condition of a single battery or a battery in multi-battery power pack in which the batteries are connected in either series or parallel.
U.S. Pat. No. 4,823,086 to Whitmire et al., discloses a battery monitoring and condition indicator for a multi-battery pack in which the batteries are connected in series. The system monitors the condition of each battery in a series multi-battery pack to determine if any battery in the battery pack is faulty.
U.S. Pat. No. 5,175,531 to Whitmire et al., discloses a battery monitoring and condition indicator for a multi-battery pack in which the batteries are connected in parallel. The system monitors the condition of each battery in a multi-battery pack to determine if any battery in a parallel battery pack are faulty.
Numerous patents and designs exist in the industry that operate similar to the designs disclosed in the patents referred to above. All of these designs require multiple wire connections to the batteries (or cells) being monitored or measured. An enclosure device is also required for the measurement circuits and indicating elements.
The present invention is an improvement on all of the previous designs because it eliminates external connections, an additional enclosure is not required and, one design or embodiment of the invention is applicable for all configurations of batteries such as a single battery, series connected strings of batteries, parallel connected strings of batteries, parallel connections of series strings, or series connections of parallel strings.
Batteries connected in parallel are the more difficult application because current sensors and amplifiers are required for determining faulty batteries in addition to the measuring and comparison circuitry. The simpler methods of measuring the potential difference between the positive and negative terminals of each battery can not be used to indicate the condition of a single battery within the battery pack. Since the voltage of the battery in best condition will be indicated when the potential difference of each battery in the battery pack is measured, methods that measure the current of each battery must be used. These methods are less preferable due the additional attendant current sensors and amplifiers.
It is therefore the principal object of the present invention to provide an improved modification to a standard battery for indicating the operating condition of an individual battery.
A further object of the present invention is to provide an improved means for determining the condition of an individual battery in a series or parallel multi-battery pack, or variations of series and parallel connections.
In addition, an object of the present invention is to provide a means to eliminate the need to monitor the battery current to indicate the status of a battery in a parallel multi-battery pack.